worried about Harry

Harry has a heart murmur which means he could just collapse at any moment, and he's been missing for more than 48 hours now, and it's raining and cold. We last saw him on Friday morning. He's been on medication for a couple of months now, and has been a lot happier since he's been taking it - all his fur has grown back on his bald patches, and he's been rubbing round us and purring a lot. (I can't bear to use past tense.)

We've just been out and put up posters with a description and this photo, in case he is locked in someone's garage or shed. I put notes through the doors of people in our close on Sunday morning before we went off to chapel, but haven't heard anything. I've also phoned the RSPCA, the Vet Line, and the people who fitted his microchip, but no-one has taken him there. Various people we have spoken to have told us tales of cats that went missing for three weeks, so it's not time to give up hope yet.

The problem is that we just don't know what has happened to him, whether or not to mourn. We keep looking at places in the house and garden where he likes to sit - his favourite cushions and places he likes to sit outside - next door's extension roof, the top of the coal shed - and every time we eat anything that we would normally give him a titbit of, it brings it home that he is not there.

Any prayers or good vibes would be much appreciated.